def demo1():
    print("Hello world!")


class Dog(object):
    color = "red"

    def __init__(self, username, age):
        self.age = age
        self.username = username

    def out_print(self):
        print("Color: %s \t age: %d \t username: %s" % (self.color, self.age, self.username))


print(__name__)
